The invention relates to an apparatus for transporting empty winding tubes from a tube magazine and onto the transport mandrels of a transport carriage.
Apparatus of the described type are used to ensure a continuous winding operation in yarn spinning plants. To this end, it is necessary to continuously provide the winding takeup machines of these spinning plants with empty yarn winding tubes at the end of each winding cycle, since the yarns to be wound advance continuously to their respective winding positions.
In general, each winding spindle of a takeup machine is equipped with one or with several winding tubes, and one yarn advances to each of these winding tubes. The exchange of the full packages from each winding spindle for a corresponding number of empty tubes is performed fully automatically, so as to be able to wind within the shortest period of time the continuously advancing yarns on the empty tubes without an unnecessary waste of yarn.
DE-OS 29 39 675 and corresponding U.S. Pat. No. 4,340,187 disclose a package doffer for such a spinning plant, in which a yarn service carriage is provided for movement in the service aisle from one takeup machine to another. The yarn service carriage is operatively linked to a package doffing carriage. When in use at each contacted and serviced takeup machine, the full packages are removed from the winding spindle and transferred to the package doffing carriage which then delivers the packages to a package transport device. The package transport device receives a plurality of packages, which it subsequently transports to an individual control station. Thereafter, the full packages having been found satisfactory, advance to a packing station.
The doffing of the full packages and replacement with empty tubes are performed by a doffer. As used in the present application, a doffer is understood to be an apparatus traveling along the machine front from one takeup machine to another, which doffs the produced full packages at the end of a winding cycle. This doffing includes the removal of the full packages from each winding spindle, and the transfer of the full packages to a carriage for further transportation.
The time to doff the produced full packages is monitored by the doffer, it being useful that the doffer also requests the respectively needed number of empty tubes.
In one embodiment, the doffer is additionally designed to furnish the just serviced winding spindle with new empty tubes after removing and transferring the full packages, so that the takeup machine is able to continue its winding operation. Such a doffer is known, for example, from DE-AS 24 49 415. In the case of this doffer, the necessary number of needed empty tubes is continuously furnished by means of a conveyor chain passing by the doffer.
Also known from DE-OS 21 28 974 is a package doffing carriage which replaces full packages with empty tubes. In this embodiment, the empty tubes are carried along on the package doffing carriage and transferred to the winding spindle of the takeup machine by means of two gripping arms.
DE-OS 21 23 689 also discloses a traveling package doffer, which delivers the full packages to a traveling package transport device. Subsequently, the package transport device is moved to an individual control station, where the individual packages are subjected either individually or randomly to a quality check, and then continue to a packing station.
In light of this prior art, it is the object of the present invention to improve the apparatus for loading empty winding tubes such that it is possible to fully automatically introduce the tubes into an operation for processing continuously advancing yarns, in particular, synthetic filament yarns. A further object resulting therefrom is to improve the apparatus such that it can be used in a spinning installation for an uninterrupted production of a plurality of synthetic filament yarns.